I don't think it's a helipad though, or that it descends underground like in Akira, because in the inside of the circle seems to be the exact same
dirt texture as on the outside of the circle. Shouldn't a helipad be more than just a circle painted on the ground?

I think it's some kind of ruined tower from long ago or something similar.

This content community relies on user-generated content from our member contributors. The opinions of our members are not those of site ownership who maintains strict editorial agnosticism and simply provides a collaborative venue for free expression.